VERITAS Storage Foundation 4.1 Intelligent Storage Provisioning Administrator's Guide

154 VERITAS Storage Foundation ISP Administrator’s Guide
In the table, the precedence order symbols have the following meaning:
For example, the default behavior of ISP (equivalent to setting
allocation_policy_order=7), A < S < T < D, means:
If a set of capabilities are specified for a volume during creation, ISP may find that there are
multiple sets of templates that provide the same set of capabilities. These sets are referred to as
template combinations. Some of the available template combinations may provide additional
capabilities (extraneous capabilities) to those that were requested for the volume. By preferring not
to select a different template combination, you can avoid implicitly specifying the extraneous
capabilities. This assumes that you would request these capabilities explicitly if you required them.
The templates that are associated with a storage pool define the characteristics of the volumes that
can be created in that pool. The selfsufficient policy of the storage pool allows you to
control whether ISP can redefine the pool definition automatically, and, if so, to what extent.
Symbol Description
A Autogrow: If permitted by the value of the AutoGrow setting, the storage pool may be grown
to increase the available storage.
D Desired Rules: Rules may be dropped if insufficient storage is available.
S Self-Sufficient: If permitted by the value of the SelfSufficent setting, templates may be
added to the storage pool if insufficient storage is available.
T Template Combination: Different template combinations may be used if insufficient storage is
available.
< Indicates the precedence in choosing an action when attempting to allocate storage. “X < Y”
means that Y is chosen in preference to X. The rightmost items in the list are chosen before
those to the left.
T < D First, drop desired rules in preference to using a different template combination.
S < T Secondly, use a different template combination in preference to adding more templates to the
storage pool.
A < S Finally, add more templates to the storage pool in preference to growing the storage pool.